Rhubarb Upside-Down Cake, Redux

Rhubarb Upside-Down Cake, Redux

Ingredients:

For the crumb topping (bottoming?  it is upside-down, after all):

• 1/2 cup white whole wheat flour
• 3 Tablespoons sugar
• 1/4 teaspoon salt
• 3 Tablespoons unsalted butter, melted

For the cake:

• Unsalted butter to grease the pan + 3 Tablespoons + 1/2 cup unsalted butter, room temperature, divided
• 1 pound (or a little extra) rhubarb, ends trimmed and cut into lengths at an angle (vary the lengths between 3-6″)
• 1-1/4 cups sugar, divided
• 1-1/2 cups white whole wheat flour
• 1-1/2 teaspoons baking powder
• 1-1/2 teaspoons salt
• 2 eggs
• Zest of one medium-sized orange
• 1 Tablespoon freshly-squeezed orange juice
• 1 cup buttermilk

Instructions:

To make the crumb topping, stir the flour, sugar, and salt together in a bowl with a fork.  Pour the melted butter over the mixture, and stir it in with the fork.  Refrigerate until needed.

Preheat the oven to 350°.  Cut a circle of parchment paper to fit the bottom of a 9″ springform pan and place the paper in the pan.  Butter (or oil, if you’d prefer) the sides of the pan and the parchment on the bottom.  Dot the parchment paper with 3 tablespoons of the butter.

Toss the rhubarb in a bowl with 1/2 cup of the sugar and set aside.

Combine the flour, baking powder, salt, and orange zest in a bowl and set aside.

In the bowl of a stand mixer with the paddle attachment, beat the remaining 1/2 cup of butter and the remaining 3/4 cup sugar until light and fluffy, about a minute.  Add the eggs one at a time, beating after each one and scraping the bowl down as needed.  Beat in the orange zest and juice.  Beat in the flour mixture in three additions, alternating with the buttermilk in two additions.  Only beat until the batter is consistent and the ingredients are incorporated.

Toss the rhubarb and sugar again, then arrange the rhubarb sections on the bottom of the springform pan, all facing in one direction.  Sprinkle with the sugar that remained in the bowl.  Pour the batter evenly over the rhubarb stalks.  Remove the crumb topping from the fridge and use a fork to help break it up into pea-sized pieces.  Scatter the crumb topping evenly over the batter.  Bake for about an hour, until the top is lightly golden and a toothpick inserted near the center comes out clean.

Cool the cake in the springform pan on a wire rack for 10 minutes, then carefully remove the sides of the pan.  Flip the cake rhubarb-side-up onto another cooling rack (I did this by sandwiching the cake between the cooling racks and carefully flipping the whole works).  Remove the bottom of the pan, which is now on the top of the cake, and let the cake cool completely on the rack unless you’re serving it immediately.

The cake keeps for about 2-3 days in an airtight container at room temperature.